TOXINS. 175 



A curious and unexplained effect of some toxins is the 

 production of minute areas of necrosis in certain viscera, as 

 the liver. Such " focal necroses " have been observed to 

 be formed by the poisons of the bacilli of diphtheria, of 

 typhoid fever, and of the micrococcus lanceolatus (of pneu- 

 monia), and following the injection of abrin and ricin. 



Besides the poisonous substances produced by the bacilli 

 of diphtheria and of tetanus, toxic substances have been 

 obtained from the spirillum of cholera, the bacillus of ty- 

 phoid fever, the bacillus coli communis, the bacillus of 

 bubonic plague, and from the bacilli of tuberculosis and 

 glanders. The extract from cultures of tubercle bacilli, called 

 tuberculin, and that from glanders bacilli, called mallein, 

 contain toxins produced by these germs, and will be spoken 

 of in connection with the bacteria themselves. Vaughan 1 

 has succeeded in cultivating anthrax bacilli, colon bacilli, 

 and other bacteria on large surfaces of solid media, so as to 

 secure quantities of the bacterial cells sufficient for extensive 

 chemical tests. The toxin of the colon bacillus proved to be 

 a very stable substance, and resistant to heat. Most toxins 

 become inactive at comparatively low temperatures. (60 

 to 70 C.) 



Prudden and Hodenpyl found that the injection of dead 

 tubercle bacilli was followed by the development of lesions 

 resembling tubercles, which, of course, did not increase in 

 number or become disseminated. 



There is good reason on both clinical and experimental 

 grounds to believe that toxic substances are formed by the 

 micrococcus lanceolatus (of pneumonia). The symptoms 

 of a disease as it occurs in man cannot be imitated in any 

 other case as accurately as happens after the injection of the 

 toxins of tetanus and diphtheria in the lower animals. 



1 American Medicine, May 18, 1901. Journal American Medical Asso- 

 ciation, March 28, 190.3. 



